From 242f92b490a695fbab244af5bad11b71f897c732 Mon Sep 17 00:00:00 2001 From: Alan Coopersmith Date: Sat, 9 Mar 2013 22:55:23 -0800 Subject: integer overflow in XIGetProperty() [CVE-2013-1984 5/8] If the number of items reported by the server is large enough that it overflows when multiplied by the size of the appropriate item type, then memory corruption can occur when more bytes are copied from the X server reply than the size of the buffer we allocated to hold them. Reported-by: Ilja Van Sprundel Signed-off-by: Alan Coopersmith Reviewed-by: Peter Hutterer --- src/XIProperties.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/src/XIProperties.c b/src/XIProperties.c index 5e58fb6..32436d1 100644 --- a/src/XIProperties.c +++ b/src/XIProperties.c @@ -38,6 +38,7 @@ #include #include #include "XIint.h" +#include Atom* XIListProperties(Display* dpy, int deviceid, int *num_props_return) @@ -170,7 +171,7 @@ XIGetProperty(Display* dpy, int deviceid, Atom property, long offset, { xXIGetPropertyReq *req; xXIGetPropertyReply rep; - long nbytes, rbytes; + unsigned long nbytes, rbytes; XExtDisplayInfo *info = XInput_find_display(dpy); @@ -216,9 +217,11 @@ XIGetProperty(Display* dpy, int deviceid, Atom property, long offset, * recopy the string to make it null terminated. */ - nbytes = rep.num_items * rep.format/8; - rbytes = nbytes + 1; - *data = Xmalloc(rbytes); + if (rep.num_items < (INT_MAX / (rep.format/8))) { + nbytes = rep.num_items * rep.format/8; + rbytes = nbytes + 1; + *data = Xmalloc(rbytes); + } if (!(*data)) { _XEatDataWords(dpy, rep.length); -- cgit v1.2.3